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The impact of piezosensitive microorganisms is generally underestimated in the ecology of underwater environments exposed to increasing hydrostatic pressure (HP), including the biodegradation of crude oil components. Yet, no isolated pressure-loving (piezophile) microorganism grows optimally on hydrocarbons, and no isolated piezophile at all has a HP optimum <10 MPa (e.g. 1000 m below sea water level). Piezosensitive heterotrophs are thus largely accountable for oil clean up < 10 MPa, however, they are affected by such a mild HP increase in ways which are not completely clear. In a first study, the application of a bioelectrochemical system (called "oil-spill snorkel") enhanced the alkane oxidation capacity in sediments collected at surface water but tested up to 10 MPa. Here, the fingerprint left on transcript abundance was studied to explore which metabolic routes are 1) supported by snorkels application and 2) negatively impacted by HP increase. Transcript abundance was comparable for beta-oxidation across all treatments (also at a taxonomical level), while the metabolism of acetyl-CoA was highly impacted: at either 0.1 or 10 MPa, snorkels supported acetyl-CoA oxidation within the TCA cycle, while in negative controls using non-conductive rods several alternative routes for acetyl-CoA were stimulated (including those leading to internal carbon reserves e.g. 2,3 butanediol and dihydroxyacetone). In general, increased HP had opposite effects as compared to snorkels, thus indicating that snorkels could enhance hydrocarbons oxidation by alleviating in part the stressing effects imposed by increased HP on the anaerobic, respiratory electron transport chain. 16S rRNA gene analysis of sediments and biofilms on snorkels suggest a crosstalk between oil-degrading, sulfate-reducing microorganisms and sulfur oxidizers. In fact, no sulfur was deposited on snorkels, however, iron, aluminum and phosphorous were found to preferentially deposit on snorkels at 10 MPa. This data indicates that a passive BES such as the oil-spill snorkel can mitigate the stress imposed by increased HP on piezosensitive microorganisms (up to 10 MPa) without being subjected to passivation. An improved setup applying these principles can further support this deep-sea bioremediation strategy.
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Poluição por Petróleo , Petróleo , Acetilcoenzima A , Alcanos , Biodegradação Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos/metabolismo , Pressão Hidrostática , Petróleo/metabolismo , RNA Ribossômico 16S/genética , RespiraçãoRESUMO
INTRODUCTION: Spider bites are common worldwide. Frequently symptoms resolve without any adverse outcome, but in rare cases the bite can cause severe morbidity. The most typical presentation of Mediterranean recluse spider (Loxosceles Rufescens) bite is a dermatonecrotic lesion of the skin (skin loxoscelism). When the only manifestation of a spider bite is an ulcerated skin lesion, clinical suspicion and differential diagnosis strongly depend on its site. We present the case of an ulcerated wound of the breast, diagnosed as a Mediterranean recluse spider bite. CASE PRESENTATION: A 79-year-old woman presented a 10cm-wide soft tissue ulceration of her left breast. At first, the diagnostic hypothesis of an ulcerated cancer was ruled out. Two family members revealed a recent history of Mediterranean recluse spider bite and the same clinical diagnosis was made for our patient. A wide excision was performed, with complete resolution of symptoms. DISCUSSION: No specific diagnostic criteria for spider bites are available. Diagnosis is usually clinical. Skin loxoscelism could be easily mistaken for cellulitis, various types of skin infections, cutaneous anthrax, vasculitis, scorpion sting, pyoderma gangrenosum, erythema migrans of Lyme disease or prurigo nodularis. A thorough anamnestic interview is fundamental to raise the diagnostic hypothesis. When possible, a biopsy is recommended and it is extremely important when the ulcer can mimic a cancer, as is the case in breast tissue. CONCLUSION: We recommend a wide excision of the wound after failure of conservative treatment, in order to obtain local control and to perform histological examination on a more representative specimen.
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Pioderma Gangrenoso , Úlcera , Idoso , Mama , Diagnóstico Diferencial , Feminino , Humanos , PeleRESUMO
BACKGROUND: In patients with obstructive sleep apnea syndrome (OSAS), repetitive hypoxia due to sleep-induced apnea adversely affects the interaction between myocardial oxygen demand and supply, resulting in the development of subclinical cardiac dysfunction. The purpose of the study was to analyze the different involvement of left and right heart myocardial function in patients with OSAS treated with noninvasive ventilation (NIV). METHODS: Conventional Doppler echocardiography, Doppler myocardial imaging (DMI), and two-dimensional speckle tracking echocardiography (2DSTE) of left (LV) and right ventricular (RV) longitudinal and right atrial (RA) deformation were performed in 55 patients with OSAS undergoing NIV (M/F 38/17; mean age 67.8 ± 11.2 years). LV and RV global longitudinal strain (GLS) was calculated by averaging local strain along the entire right and left ventricle, before and during NIV, and after 6 months of nocturnal NIV therapy. RESULTS: LV morphology was comparable before and during NIV, whereas LV ejection fraction and LV DMI early diastolic peak velocity were significantly improved in patients with OSAS during NIV, as was LV regional peak myocardial strain (P < 0.001). RV diameters were slightly increased in patients with OSAS during ventilation, whereas pulmonary artery systolic pressure (PASP), RV GLS, and regional peak myocardial RV strain were significantly reduced during ventilation (P < 0.0001). RA transverse diameters and RA area were also slightly increased during NIV, whereas RA lateral wall strain was reduced (P < 0.001). Acute RV myocardial impairment completely reversed at follow-up, with a decrease in PASP and subsequent increase in both RV and RA myocardial performance. CONCLUSIONS: Conventional 2DSTE is a useful tool for assessing left and right heart morphology and myocardial deformation in patients with OSAS and for monitoring both acute and chronic effects of NIV.
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Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Ecocardiografia/métodos , Apneia Obstrutiva do Sono/diagnóstico por imagem , Apneia Obstrutiva do Sono/terapia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Doença Aguda , Idoso , Doença Crônica , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Apneia Obstrutiva do Sono/complicações , Volume Sistólico , Resultado do TratamentoRESUMO
AIMS: To elucidate right ventricular (RV) function in patients with idiopathic pulmonary fibrosis (IPF) with and without pulmonary hypertension (PH) and its relation to other features of the disease. METHODS AND RESULTS: Clinical evaluation, standard Doppler echo, Doppler myocardial imaging (DMI), and 2D strain echocardiography (STE) of RV septal and lateral walls were performed in 52 IPF patients (66.5 ± 8.5 years; 27 males) and in 45 age- and sex-comparable controls using a commercial US system (MyLab Alpha, Esaote). Pulmonary artery mean pressure (mPAP) was estimated by standard echo Doppler. RV global longitudinal strain (RV GLS) was calculated by averaging RV local strains. The IPF patients were divided into 2 groups by noninvasive assessment of PH: no PH (mPAP<25 mmHg; 36 pts) and PH (mPAP ≥25 mmHg; 16 pts). Left ventricular diameters and ejection fraction were comparable between controls and IPF, while GLS was impaired in IPF (P < 0.01). RV end-diastolic diameters, wall thickness andmPAP were increased in IPF patients with PH. In addition, pulsed DMI detected in PH IPF impaired myocardial RV early diastolic (Em) peak velocity. Also peak systolic RV strain was reduced in basal and middle RV lateral free walls in IPF, as well as RV GLS (P < 0.0001). The impairment in RV wall strain was more evident when comparing controls with the no PH group than comparing the no PH group with the PH group. By multivariate analysis, independent association of RV strain with both six-minute walking test distance (P < 0.001), mPAP (P < 0.0001), as well as with forced vital capacity (FVC) % (P < 0.005) in IPF patients were observed. CONCLUSIONS: Impaired RV diastolic and systolic myocardial function were present even in IPF patients without PH, which indicates an early impact on RV function and structure in patients with IPF.
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Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/fisiopatologia , Fibrose Pulmonar Idiopática/diagnóstico por imagem , Fibrose Pulmonar Idiopática/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia Doppler , Feminino , Humanos , Hipertensão Pulmonar/complicações , Fibrose Pulmonar Idiopática/complicações , Masculino , Pessoa de Meia-IdadeRESUMO
AIMS: Transcatheter aortic valve implantation (TAVI) is an alternative treatment in surgically high-risk or inoperable patients with severe aortic stenosis (AS). The objective of this study was to analyze the effects of TAVI on left ventricular (LV) and left atrial (LA) longitudinal function assessed by speckle tracking echocardiography (2DSTE) in patients with AS. METHODS: In our prospectively conducted study, a total of 55 symptomatic (New York Heart Association class II or higher) patients with severe AS, considered to be at increased risk for undergoing surgical aortic valve replacement, were recruited (age: 78.6 ± 7.4 year). Patients underwent a complete clinical and laboratory evaluation, in addition to standard echocardiography and 2DSTE. Echocardiographic analysis was performed before and 6 months after TAVI. 2DSTE measured segmental and global longitudinal strain (GLS) and radial strain. RESULTS: All the patients received the CoreValve self-expanding prosthesis. Six months after TAVI, patients showed a significant reduction in mean transaortic gradient (52.1 ± 15.8 vs. 11.2 ± 3.3 mmHg, P < 0.0001), LV mass, LA volume index, and an improvement of ejection fraction (P < 0.0001). In addition, LV GLS (-11.8 ± 3.2 vs. -16.3 ± 4.2%; P < 0.0001) and LA longitudinal strain (14.2 ± 5.4 vs. 26.6 ± 10.8%, P < 0.0001) significantly increased after TAVI. In a stepwise forward multiple logistic regression analysis, LV mass before TAVI (P < 0.001) and peak CK MB mass after TAVI (P < 0.0001) were powerful independent predictors of lower improvement of LV GLS. Moreover, LV mass index (P < 0.001) and LV GLS strain (P < 0.001) before TAVI were powerful independent predictor of LA longitudinal strain after TAVI CONCLUSIONS: TAVI in patients with AS resulted in geometric changes known as "reverse remodelling," and improved LV and LA function assessed by 2DSTE.
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Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Átrios do Coração/fisiopatologia , Substituição da Valva Aórtica Transcateter , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico por imagem , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Ultrassonografia , Disfunção Ventricular Esquerda/prevenção & controleRESUMO
BACKGROUND: Nipple adenoma is a very uncommon, benign neoplasm that involves the nipple. A palpable mass of the nipple associated with nipple discharge and erosion or ulceration is the common clinical presentation. Generally, complete surgical excision of the nipple is the main treatment, alternative therapeutic methods such as Mohs micrographic surgery, nipple splitting enucleation, and cryotherapy can be considered. Disorders of the breast in young women are generally benign. Even if the management during pregnancy is usually conservative and surgical excision is reserved for very strong malignancy suspicion, benign lesions can cause the impossibility to breastfeed after giving birth when involving the nipple. CASE PRESENTATION: We present the case of a 28-year-old female, who was referred to the Breast Unit of the University Hospital of Modena (Italy) in May 2020 with a 12-months history of enlargement of the left nipple with associated erythema, serohemorrhagic discharge, and pain in the left nipple region. The diagnostic assessment came out in favor of a nipple adenoma. After surgical treatment was recommended, the patient got pregnant. Taking into account the major risks of surgery during pregnancy, a multidisciplinary discussion was conducted, to consider whether to proceed with surgery or postpone it after pregnancy. Because of the volume and the position of the adenoma, the indication for surgical excision was confirmed, to allow regular lactation and breastfeeding immediately after giving birth and to avoid potential obstructive complications. Surgical excision of nipple adenoma without complete resection of the nipple was performed after her first trimester of pregnancy under local anesthesia. A histopathological examination confirmed the diagnosis. No recurrence occurred after 12 months. The patient gave birth, had no deficit in lactation, and successfully breastfed. CONCLUSIONS: Therefore, we consider that nipple adenoma enucleation might be a safe treatment even during pregnancy. Moreover, conservative local treatment of nipple adenomas can preserve the nipple aesthetically and functionally, thus allowing regular lactation and breastfeeding in young women.
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Adenoma , Mamilos , Feminino , Gravidez , Humanos , Adulto , Mamilos/patologia , Mamilos/cirurgia , Aleitamento Materno , Adenoma/cirurgia , Adenoma/patologia , PartoRESUMO
Germline pathogenic variants (PV) of the PALB2 tumor suppressor gene are associated with an increased risk of breast, pancreatic, and ovarian cancer. In previous research, PALB2-associated breast cancer showed aggressive clinicopathological phenotypes, particularly triple-negative subtype, and higher mortality regardless of tumor stage, type of chemotherapy nor hormone receptor status. The identification of this germline alteration may have an impact on clinical management of breast cancer (BC) from the surgical approach to the systemic treatment choice. We herein report the case of a patient with a germline PV of PALB2, diagnosed with locally advanced PD-L1 positive triple-negative BC, who progressed after an immune checkpoint inhibitor (ICI)-containing regimen and then experienced a pathologic complete response after platinum-based chemotherapy. This case report hints a major role of the germline PALB2 alteration compared to the PD-L1 expression as cancer driver and gives us the opportunity to extensively review and discuss the available literature on the optimal management of PALB2-associated BC. Overall, our case report and review of the literature provide additional evidence that the germline analysis of PALB2 gene should be included in routine genetic testing for predictive purposes and to refine treatment algorithms.
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Ewing's Sarcoma Family Tumors (ESFT) include classic Ewing's sarcoma of bone, extra-skeletal Ewing's sarcoma (EES), malignant small cell tumor of the chest wall (Askin tumor), and soft tissue-based Peripheral Primitive Neuroectodermal tumors (pPNET). The t(11;22)(q24;q12) translocation is associated with 85% of tumors and leads to EWS-FLI-1 (Ewing's Sarcoma-Friend Leukemia Integration-1) formation. This is a potent transforming gene that encodes a chimeric protein that plays a role in the genesis of Ewing's Sarcoma and Primitive Neuroectodermal Tumors. The breast location of ESFT remains exceptional. The prognosis is among the poorest of all subtypes of breast cancer and even poorer than other extraosseous Ewing's sarcomas. We describe the case report of a 23-year-old patient with a growing breast lump, who required an accurate and challenging diagnostic estimation and who ultimately resulted in a peripheral primary neuroectodermal tumor (pPNET). Through this case description and a brief narrative review of the literature, we aim to highlight the rarity of ESFT located in the breast. Histopathological confirmation is mandatory for all growing masses of the breast to reach a conclusive diagnosis and plan the correct treatment. Patients with rare diagnoses should always be centralized in breast units, conducting multidisciplinary meetings and, when necessary, the diagnosis should be shared through wider national or international registries.
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Pressão Positiva Contínua nas Vias Aéreas/efeitos adversos , Ecocardiografia/métodos , Apneia Obstrutiva do Sono/diagnóstico por imagem , Apneia Obstrutiva do Sono/terapia , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Doença Aguda , Idoso , Doença Crônica , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Medição de Risco , Sensibilidade e Especificidade , Apneia Obstrutiva do Sono/complicações , Volume Sistólico , Resultado do TratamentoRESUMO
INTRODUCTION: Almost 50% to 70% of patients who undergo axillary lymph node dissection (ALND) because of a single metastatic sentinel lymph node (SLN) have no further metastatic nodes at the axillary histology. On these grounds, the one-step nucleic acid amplification (OSNA) nomogram was designed and validated. As a mathematical model, calculated through tumor size (expressed in millimeters) and CK19 mRNA copy number, it is thought to predict nonsentinel lymph node (NSLN) status. The aim of the study is to verify the diagnostic accuracy of the OSNA nomogram in a group of patients with macrometastatic SLN, with a retrospective analysis. METHODS: The OSNA nomogram was retrospectively applied to a group of 66 patients with macrometastatic SLN who underwent ALND. The result of the final histology of the axillary cavity was compared to the nomogram prediction. We calculated the prevalence of NSLN metastasis in patients who underwent ALND, sensitivity and specificity, negative and positive predictive value of the nomogram. RESULTS: In patients with macrometastasis in SLN, the prevalence of patients with metastatic NSLN was 45%. The sensitivity of the nomogram was excellent (90%). The specificity was low (36%). Positive predictive value amounted to 54%, while negative predictive value was good (81%). CONCLUSIONS: These results suggest that the OSNA nomogram is a valid instrument that can help choose the best surgical strategy for the treatment of axillary cavity. The mathematical model is useful to avoid surgery in a selected group of patients because it accurately predicts NSLN status.
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Degradation of petroleum hydrocarbons (HC) in sediments is often limited by the availability of electron acceptors. By allowing long-distance electron transport (LDET) between anoxic sediments and oxic overlying water, bioelectrochemical snorkels may stimulate the regeneration of sulphate in the anoxic sediment thereby accelerating petroleum HC degradation. Cable bacteria can also mediate LDET between anoxic and oxic sediment layers and thus theoretically stimulate petroleum HC degradation. Here, we quantitatively assessed the impact of cable bacteria and snorkels on the degradation of alkanes in marine sediment from Aarhus Bay (Denmark). After seven weeks, cable bacteria and snorkels accelerated alkanes degradation by +24 and +25%, respectively, compared to control sediment with no cable bacteria nor snorkel. The combination of snorkels and cable bacteria further enhanced alkanes degradation (+46%). Higher degradation rates were sustained by LDET-induced sulphide removal rather than, as initially hypothesized, sulphate regeneration. Cable bacteria are thus overlooked players in the self-healing capacity of crude-oil contaminated sediments, and may inspire novel remediation treatments upon hydrocarbon spillage.
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Poluição por Petróleo , Petróleo , Bactérias , Biodegradação Ambiental , Descontaminação , Dinamarca , Sedimentos Geológicos , HidrocarbonetosRESUMO
The areas in which Stromal Vascular Fraction cells (SVFs) have been used include radiotherapy based tissue damage after mastectomy, breast augmentation, calvarial defects, Crohn's fistulas, and damaged skeletal muscle. Currently, the authors present their experience using regenerative cell therapy in breast reconstruction. The goal of this study was to evaluate the safety and efficacy of the use of Engineered Fat Graft Enhanced with Adipose-derived Stromal Vascular Fraction cells (EF-e-A) in breast reconstruction. 121 patients that were affected by the outcomes of breast oncoplastic surgery were treated with EF-e-A, comparing the results with the control group (n = 50) treated with not enhanced fat graft (EF-ne-A). The preoperative evaluation included a complete clinical examination, a photographic assessment, biopsy, magnetic resonance (MRI) of the soft tissue, and ultrasound (US). Postoperative follow-up took place at two, seven, 15, 21, 36 weeks, and then annually. In 72.8% (n = 88) of breast reconstruction treated with EF-e-A, we observed a restoration of the breast contour and an increase of 12.8 mm in the three-dimensional volume after 12 weeks, which was only observed in 27.3% (n = 33) of patients in the control group that was treated with EF-ne-A. Transplanted fat tissue reabsorption was analyzed with instrumental MRI and US. Volumetric persistence in the study group was higher (70.8%) than that in the control group (41.4%) (p < 0.0001 vs. control group). The use of EF-e-A was safe and effective in this series of treated cases.
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Mammary tuberculosis is exceptional in developed countries. It can mimic an abscess or a granulomatous mastitis. In subjects coming from endemic areas, it is necessary to suspect a tuberculosis infection in case of recurrent mastitis refractory to antibiotics. Positivity of Quantiferon-TB Gold assay can help to confirm the clinical suspicion.
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Microbial electrochemical technologies (MET) are increasingly being considered for in situ remediation of contaminated groundwater. However, their application potential for the simultaneous treatment of complex mixtures of organic and inorganic contaminants, has been only marginally explored. Here we have analyzed the performance of the 'bioelectric well', a previously developed bioelectrochemical reactor configuration, in the treatment of benzene, toluene, ethyl-benzene and xylenes (BTEX) mixtures. Although to different extents, all BTEX were found to be degraded in the bioelectrochemical system, operated using a continuous-flow of groundwater at a hydraulic retention time of 8.8â¯h, with the graphite anode potentiostatically controlled at +0.200â¯V vs. the standard hydrogen electrode. In the case of toluene and ethyl-benzene, biodegradation was further confirmed by the GC-MS identification of fumarate-addition metabolites, previously shown to be involved in the activation of these contaminants under anaerobic conditions. Degradation rates were higher for toluene (31.3⯱â¯1.5â¯mg/L d) and lower for benzene (6.1⯱â¯0.3â¯mg/L d), ethyl-benzene (3.3⯱â¯0.1â¯mg/L d), and xylenes (4.5⯱â¯0.2â¯mg/L d). BTEX degradation was linked to electric current generation, with coulombic efficiencies falling in the range 53-69%, although methanogenesis also contributed to contaminant degradation. Remarkably, the system also allowed removal of sulfate simultaneously with toluene. Sulfate removal was likely driven by the hydrogen abiotically generated at the cathode. Taken as a whole, these findings highlight the remarkable potential of this innovative reactor configuration for application in a variety of contamination scenarios.
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Benzeno/metabolismo , Reatores Biológicos , Técnicas Eletroquímicas , Água Subterrânea/química , Sulfatos/metabolismo , Tolueno/metabolismo , Poluentes Químicos da Água/metabolismo , Xilenos/metabolismo , Benzeno/química , Biodegradação Ambiental , Sulfatos/química , Tolueno/química , Poluentes Químicos da Água/química , Xilenos/químicaRESUMO
Post-surgical pyoderma gangrenosum (PSPG) of the breast is a rare dermatosis that worsens surgical manipulation, with a chronical relapsing course. Diagnosis is mostly clinical and made by exclusion after the failure of antibiotic therapies and surgical debridement, while the mainstay of therapy is corticosteroid-based. Here we report a case of PSPG of the breast in a young woman with breast cancer, to emphasize the needs of an early and accurate diagnosis, to guarantee the most efficacious treatment and to avoid life-threatening complications.
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Doenças Mamárias/diagnóstico , Doenças Mamárias/etiologia , Mastectomia Segmentar/efeitos adversos , Pioderma Gangrenoso/diagnóstico , Pioderma Gangrenoso/etiologia , Doenças Mamárias/tratamento farmacológico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mamoplastia/efeitos adversos , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Pioderma Gangrenoso/tratamento farmacológicoRESUMO
Groundwater contamination by petroleum hydrocarbons (PHs) is a widespread problem which poses serious environmental and health concerns. Recently, microbial electrochemical technologies (MET) have attracted considerable attention for remediation applications, having the potential to overcome some of the limiting factors of conventional in situ bioremediation systems. So far, field-scale application of MET has been largely hindered by the limited availability of scalable system configurations. Here, we describe the 'bioelectric well' a bioelectrochemical reactor configuration, which can be installed directly within groundwater wells and can be applied for in situ treatment of organic contaminants, such as PHs. A laboratory-scale prototype of the bioelectric well has been set up and operated in continuous-flow regime with phenol as the model contaminant. The best performance was obtained when the system was inoculated with refinery sludge and the anode potentiostatically controlled at +0.2 V versus SHE. Under this condition, the influent phenol (25 mg l-1 ) was nearly completely (99.5 ± 0.4%) removed, with an average degradation rate of 59 ± 3 mg l-1 d and a coulombic efficiency of 104 ± 4%. Microbial community analysis revealed a remarkable enrichment of Geobacter species on the surface of the graphite anode, clearly pointing to a direct involvement of this electro-active bacterium in the current-generating and phenol-oxidizing process.
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Biodegradação Ambiental , Técnicas Eletroquímicas/métodos , Água Subterrânea/química , Hidrocarbonetos/metabolismo , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Reatores Biológicos/microbiologia , Biotransformação , Eletrodos/microbiologia , Esgotos/microbiologiaRESUMO
Growing scientific interest in mixed microbial culture-based anaerobic biotechnologies for the production of value-added chemicals and fuels from organic waste residues requires a parallel focus on the development and implementation of strategies to control the distribution of products. This study examined the feasibility of an electrofermentation approach, based on the introduction of a polarized (-700â mV vs. the standard hydrogen electrode) graphite electrode in the fermentation medium, to steer the product distribution during the conversion of organic substrates (glucose, ethanol, and acetate supplied as single compounds or in mixtures) by undefined mixed microbial cultures. In batch experiments, the polarized electrode triggered a nearly 20-fold increase (relative to open circuit controls) in the yield of isobutyrate production (0.43±0.01 vs. 0.02±0.02â mol mol-1 glucose) during the anaerobic fermentation of the ternary mixture of substrates, without adversely affecting the rate of substrate bioconversion. The observed change in the fermentative metabolism was most likely triggered by the (potentiostatic) regulation of the oxidation-reduction potential of the reaction medium rather than by the electrode serving as an electron donor.
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Fontes de Energia Bioelétrica/microbiologia , Fermentação , Compostos Orgânicos/metabolismo , Técnicas de Cultura , EletroquímicaRESUMO
BACKGROUND: Recent studies have suggested that addition of electrically conductive biochar particles is an effective strategy to improve the methanogenic conversion of waste organic substrates, by promoting syntrophic associations between acetogenic and methanogenic organisms based on interspecies electron transfer processes. However, the underlying fundamentals of the process are still largely speculative and, therefore, a priori identification, screening, and even design of suitable biochar materials for a given biotechnological process are not yet possible. RESULTS: Here, three charcoal-like products (i.e., biochars) obtained from the pyrolysis of different lignocellulosic materials, (i.e., wheat bran pellets, coppiced woodlands, and orchard pruning) were tested for their capacity to enhance methane production from a food waste fermentate. In all biochar-supplemented (25 g/L) batch experiments, the complete methanogenic conversion of fermentate volatile fatty acids proceeded at a rate that was up to 5 times higher than that observed in the unamended (or sand-supplemented) controls. Fluorescent in situ hybridization analysis coupled with confocal laser scanning microscopy revealed an intimate association between archaea and bacteria around the biochar particles and provided a clear indication that biochar also shaped the composition of the microbial consortium. Based on the application of a suite of physico-chemical and electrochemical characterization techniques, we demonstrated that the positive effect of biochar is directly related to the electron-donating capacity (EDC) of the material, but is independent of its bulk electrical conductivity and specific surface area. The latter properties were all previously hypothesized to play a major role in the biochar-mediated interspecies electron transfer process in methanogenic consortia. CONCLUSIONS: Collectively, these results of this study suggest that for biochar addition in anaerobic digester operation, the screening and identification of the most suitable biochar material should be based on EDC determination, via simple electrochemical tests.
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AIMS: To analyse right ventricular (RV) systolic function in patients with hypertrophic cardiomyopathy (HCM) at rest and during exercise, and its possible correlation with left ventricular(LV) morphology and function. METHODS AND RESULTS: Standard echo, exercise stress echo, and RV 2D speckle-tracking strain (2DSE) were performed in 45 patients with HCM and in 45 age- and sex-comparable healthy controls. RV global longitudinal strain (GLS) was calculated by averaging local strains along the entire right ventricle. LV mass index and IVS wall thickness were significantly increased in HCM, while LV ejection fraction, RV diameters, RV tissue Doppler systolic peak and the RV end-systolic pressure-area relationship at rest were comparable between the two groups. Conversely, all transmitral Doppler indexes were significantly impaired in HCM. In addition, RV GLS and regional peak myocardial RV strains were significantly reduced in patients with HCM (all P<0.001). During physical effort, LV ejection fraction was comparable between the two groups. Conversely, LV E/Em ratio was significantly increased in HCM. Increase in TAPSE and RV tissue Doppler Sm peak velocity during effort were similar between the two groups. Conversely, increases of RV end-systolic pressure-area, regional and global RV strain were significantly lower in HCM patients (RV lateral strain: 10.3±3.5% of increase in HCM vs 20.5±4.5% in controls; p<0.0001). Multivariable analysis detected independent associations of RV lateral strain at peak stress with LV IVS thickness, maximal workload during exercise, and LV E/Em ratio during effort (all p<0.0001). An RV lateral 2DSE cut-off point of -14% differentiated controls and HCM with an 86%sensitivity and a 92% specificity. CONCLUSIONS: RV contractile reserve for HCM is impaired and this suggests that the lower resting values of RV in HCM may represent early subclinical myocardial damage, closely associated with exercise capacity.
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Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Ecocardiografia sob Estresse , Interpretação de Imagem Assistida por Computador , Contração Miocárdica/fisiologia , Disfunção Ventricular Direita/diagnóstico por imagem , Adulto , Cardiomiopatia Hipertrófica/fisiopatologia , Estudos de Casos e Controles , Ecocardiografia , Feminino , Reserva Fracionada de Fluxo Miocárdico/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Variações Dependentes do Observador , Curva ROC , Valores de Referência , Descanso , Índice de Gravidade de Doença , Disfunção Ventricular Direita/fisiopatologia , Adulto JovemRESUMO
Primary cardiac paragangliomas are extremely rare. Recently this neoplasm has been associated with a familiar syndrome as a result of mutation of genes that encode proteins in the mitochondrial complex II. We report a case of a 46-year-old woman having cases of vertebral paraganglioma in her family showing an unusual anatomic and clinical presentation of cardiac paraganglioma and expressing a genetic mutation never associated before with cardiac localization of this neoplasm.